Stability of Carotenoids in Sweet Corn: Part 1. Evaluation of Postharvest Handling and Domestic Cooking

Sweet corn is a rich source of dietary carotenoids. In this study, the effects of postharvest handling and cooking on carotenoids in sweet corn were investigated. The fresh bicolor sweet corn was harvested from the field, which was processed into samples that represented the two major retail types (farmers market and grocery store) and two common cooking methods (boiling and steaming). Both free and bound forms of carotenoids were analyzed by high-performance liquid chromatography and LC–MS. Nine carotenoids were identified, with lutein and zeaxanthin being the predominant ones. The postharvest handling and cooking either did not change or reduced the free carotenoids but increased the total bound carotenoids. The total carotenoids in all processed samples were not altered or slightly decreased. The percentages of total bound carotenoids in total carotenoids increased in all processed and cooked samples. The changes of individual carotenoids depended on the processing/cooking methods and the chemical structures.